As portable electronic devices, such as mobile phones and tablets, are getting more computationally powerful and complex, they are also consuming more power. To accommodate these increased power demands, the energy storage capacity of the batteries used to power such devices are often correspondingly increased.
In many portable products, the Universal Serial Bus (USB) is often used both as communication port and as a power delivery port to accommodate battery charging. For example, a standard USB 2.0 compliant port may provide a maximum power delivery of 7.5 W (5V at 1.5 A) to a dedicated charging port that may be used to recharge the battery of a portable device. However, as the battery capacities of tablets devices are increasing, for example, from 5600 mAh to 8000 mAh and 10000 mAh, the charging time for these devices increase accordingly. For example, using a standard USB 2.0 compliant port, it takes about 2 hours and 40 minutes to recharge a 5600 mAh battery, but it takes 4 hours and 45 minutes to recharge a 10000 mAh.
By increasing the charging current or charging voltage, however, faster charging times may be achieved. In some cases, a “Y” connector may be used to combine the output of two USB ports to provide higher currents, or some non-standard USB-type implementations may allow for higher currents.